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open air does when of kept of in such a degree of heat
euaporate such a quanty thereof in the space of an howr. though
the same hardly becomes visible vnlesse in very cold or very
hott weather. In very cold weather by the condensation of them
into a mist and in very hott by the playing or dancing
of the air as we commonly call the vndulation of the
rising vapours ouer Riuers .

This also was partly to be ascribed to the keeping in of the vapours
of the water in wells by the air of it, wch. being once satiated
would take vp noe more vapours into it whence soe soon
as this water was Exposed to fresh air that was vnsatia
ted the vapours were taken vp more copiously by it. this
the Damps of wells sufficiently euidenced

Against this continuall euaporation of the Air Dr. Croon
alledged an Expt. of Kircher. And Sr. Iohn Hoskins affirmed the
same to be mentiond by Beregardus in his Circulus Pi
sanus, by wch. it was euident that water though exposd
to the air did not yet euaporate though kept open for
twenty years. wch. was an argument that all water did not
soe euaporate as was supposed. to

To this It was answerd that though there might be such an
Expt. made and obserued, yet that this Expt. did not ouer
throw the former supposition especially since one necessary
circumstance in the making this Expt. was that the neck
of the vessell that conteind this water must be exceeding
long & high & the hole small. soe that Little or noe
change was made of the air next the water. wch.
being once satiated would after that take vp noe more
vapours into it.

mr. Henshaw mentiond the way of rectifying Spts. & volatill salts
by very high bodys & heads to the top of wch. the Sprts. & volatill salts
would rise but the watery & flegmatique parts would not rise
half the way neer that height And that there were some volatill Salts
which would rise in a small body sooner & higher than Spt. of wine -

Ref: CELL/RS/HF_221  © Centre for Editing Lives and Letters